Understanding Mapleson Circuits Dr Anderson

Anaesthesia breathing systems An anaesthesia breathing system is a series of components that facilitates transport of gases from the anaesthesia machine to the patient

Components of an anaesthesia circuit Ports Machine to system System to patient Patient to atmosphere Gas resevior Corrugated tubing CO2 absorber

Requirements of a breathing system Quick and accurate delivery of gas CO2 elimination Minimal dead space Low resistance

Desirable attributes of a breathing system Gas economy Conservation of heat Humidification of inspired gas Lightweight Convenient Adaptable Control of pollution

Classification of circuits Open Semi Open Semi Closed

Open Systems Ether mask Insufflation advantage Disadvantage No rebreathing No reservoir bag No valves Spontaneous ventilation only FGF unrestricted Poor depth control simple pollution

Differentiation between Mapleson systems Component arrangement FGF requirements rebreathing SV/CV performance

Mapleson classification Reservoir bag on afferent limb Mapleson A, B, C Lack circuit Reservoir bag on efferent limb Mapleson D, E, F Bain circuit

A look at the functioning of the circuits

Advantages of Mapleson systems Simplicity Less effect on EtCO2 Retention of heat and moisture Less airway resistance Lightweight MRI compatable

How to test a Bain Circuit